How’s a data center going to use a lot of hot air? Maybe they could use specialized heat pumps to condense it even more and spin some turbines, but the efficiency would be extremely low and probably not worth the investment. Best option is probably to just heat a few adjacent buildings in the winter.
I understand what you’re saying, I just don’t think it’s easy to deliver such low density heat in a useful way. Large datacenters are located away from residential land because they can be unpleasant to live near, and while businesses could be close by, what industries can utilize a huge volume of ~100 degree air?